Magneto-coupling.



H. H. PIERCE.

MAGNETO COUPLING.

APPLICATION FILED Aue.29. 1918.

1,301,002., Patented Apr. 15,1919.

A TTORNEYS NT @FFEQE.

. 3mm H.- stance, on EUGENE, cane-on.

aaoaooe.

menace-comma.

Specification of Iietters Patent.

Y Application and August 29, 1618. Serial are. 251,937.

7 '0 all whom it may concern:

Be it known that I, RALPH H. Pmnoe, a-

I citizen of the United States, and a resident of Eugene, in the'county of Lane and State of Oregon, have invented anew and Improved Magneto-Coupling, of which the following is a full, clear, and exact description. V

This invention relates to an impulse coupling adapted for use in connection with a magneto to produce a hot spark at slow engine speed, as when the engine is being cranked, thereby'enabling the largest engines to be started on the magneto without the use of batteries.

The invention has for its general objects to improve and simplify the construction and operation of devices of this character so as to be reliable and efficient in use, comaratively simple and inexpensive to manuacture, and so designed as to be automatic in operation.

A more specific object of the invention is the provision of an impulse coupling of that type embodying a spring between the two sections of the coupling, with automatic dogs for. holding the armature section of t e couplin restrained while the spring is placed on er tension by the turn ing of the engine crank in starting, and when the dogs are automatically released the sprin imparts a quick impulse to the armature shaft, whereby a hot spark is produced to ignite the gas in the cylinders, the dogs having automatic means for throwing them out of operative position when the engine turns at high speed under the explo- -sive impulses; and also having means for restoring the dogs when the engine stops, so that the dogs will be ready to perform their function when the engine is again cranked.

Fig. 2 is a similar view showing the dogs engaged while the spring is being placed under tension;

Fig. 3 is a side view of the coupling; and

Fig. 4' is a central vertical section on the line 4-4:, Fig. 1. I

Referring to the drawing, A designates a magneto which may be of the high or low tension type and adapted for use in connection with an engine having any desired number of cylinders, and. to the armature shaft 1 is attached the impulse coupling B, which is connected in any suitable manner with the engine shaft 2.

. The coupling B is composed of an engine section 3 and an armature shaft section 4 of any suitable construction, the section 3 being in the form of a cap having a diametrical key lug 5 for engagement with the slotted head or member 6 of the engine shaft 2, and projecting from the periphery of the section 3 are stop lugs 7 each having a cam surface 8. The section 4 is in the form of a ring having a central hub 9 in which is keyed the armature shaft 1, and surrounding the hub is a cylindrical boss or wall 10 which loosely Patented Apr. 15, 1919.

extends into the cap section 3. A helical torsional spring 11 is housed in the boss 10 and has opposite ends 12 and 13 connected with the sections 3 and 4: of the coupling, so that by relative rotation of the sections the spring is placed under tension. On the section 4 and pivoted at diametrically opposite points 14 are dogs 15 having trailin arms 16 each provided with a weight 17 n the magneto frame is a notch, shoulder or projection 18 with which the dog 15 is adapted to engagein order to hold the section 4 of the coupling stationary while the spring 11 is being wound or placed under tension, and after the section 3 is rotated a suitable number of degrees the cam surface 8 of the nearest projection will engage the weighted end 17 and tilt the arm 16 so as to disengage the dog 15 from the projection 18. In Fig. 3 this action is about to take place, and as soon as the releasing is completed the tension of the spring 11 causes the section 4 of the coupling to rotate with a very quick impulse, whereby the armature of the magneto is caused to turn at such a speed as to produce a hot spark in the engine cylinder. The explosion now taking place will cause the engine shaft to rotate at a high'speed and the weighted arm 16 fly outwardly by centrifugal action, so

that the dogs 15 are held retracted inwardly so as not to engage the projection Suit-- able means, such as springs 19, act on the arms 16 to normally hold the weight 17 in--- wardly and the do s 15 outwardly, as when the engine is idle. When the dog is released from the projection 18 the section 4 of the coupling is thrown forwardly under the tension of the spring through a slight angle until the projections 20 on the section 4 strike the projections 7, but this movement is so quick that the current generated by the magneto is suflicient to produce a hot igniting spark.

it understood that the device shown is merely,

illustrative and that such changes may be made when desired as fall within the scope of the appended claims.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

1. A coupling of the class described, com- 7 the sections, pivoted and spring pressed prising two relatively rotatable sections, one

ofthe sections being provided with lugs having cam surfaces on one face and the other section with projections, a spring connecging wa mounted on the-section having the projections, said dogs having curved and weighted arms adapted to be engaged bv the cam surfaces of said lugs, and a fixed projection with which the dogs engage, a projection being adapted to engage the face of a lug opposite that having a cam surface when the dog is disengaged from the fixed projection.

2. A coupling of the class described, comrising a cap-like section provided with lugs aving cam surfaces on one face, a second section having a cylindrical boss fitting in the cap and provided with projections, a spring in the said boss andhaving its ends secured to .the sections, pivoted and spring pressed dogs mounted on the second section at the projections, said dogs having arms provided with weights at their ends adapted to engage the cam surfaces of the lugs, and a fixed projection with which the dogs engage, the face of 9, lug o posite the cam surface being adapted to engage a projection when the dog is disengaged from the fixed projection.

v RALPH H. PIERCE 

